<!DOCTYPE html>
<html lang="en">

<head>
  <title></title>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <!--<script src="https://unpkg.com/vue"></script>-->

  <style>
    #app:hover {

      color: red;

    }
  
  </style>

</head>

<!--<script src="./call.js"></script>-->

<body>

  <div id="app">
    发发发
  </div>

</body>

</html>

<!--<script>
  // var obj = {
  //     person: {
  //         age: '10'
  //     },
  //     sex: 'man'
  // }

  var library = {
    book1: {
      name: ''
    },
    book2: ''
  }




  function observe(data) {
    if (!data || typeof data !== 'object') {
      return;
    }
    Object.keys(data).forEach(function (key) {
      console.log(key)
    })

  }


  observe(library)




  var app = new Vue({
    el: '#app',
    data: {

      obj: {
        a: 1
      }
    },
    created() {}
  })

</script>-->
